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Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
157.5419 -51.7953 0.0096 43.9895 -0.5539 3.0014198 20.061 TRIG_00551126
Foreground time interval of the image:
1.624 60.805 (delta_t = 59.181 [sec])
Background time interval of the image:
-239.296 1.624 (delta_t = 240.920 [sec])
Lightcurves
Notes:
- 1) The mask-weighted light curves are using the flight position.
- 2) Multiple plots of different time binning/intervals are shown to cover all scenarios of short/long GRBs, rate/image triggers, and real/false positives.
- 3) For all the mask-weighted lightcurves, the y-axis units are counts/sec/det where a det is 0.4 x 0.4 = 0.16 sq cm.
- 4) The verticle lines correspond to following: green dotted lines are T50 interval, black dotted lines are T90 interval, blue solid line(s) is a spacecraft slew start time, and orange solid line(s) is a spacecraft slew end time.
- 5) Time of each bin is in the middle of the bin.
1 s binning
From T0-310 s to T0+310 s
From T100_start - 20 s to T100_end + 30 s
Full time interval
64 ms binning
Full time interval
From T100_start to T100_end
From T0-5 sec to T0+5 sec
16 ms binning
From T100_start-5 s to T100_start+5 s
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 12.160000
8 ms binning
From T100_start-3 s to T100_start+3 s
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 12.160000
2 ms binning
From T100_start-1 s to T100_start+1 s
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 12.160000
SN=5 or 10 sec. binning (whichever binning is satisfied first)
SN=5 or 10 sec. binning (T < 200 sec)
Quad-rate summed light curves (from T0-300s to T0+1000s)
The mask-weighted light curves based on cleaned DPHs
Spectral Evolution
Spectra
Notes:
- 1) The fitting includes the systematic errors.
- 2) When the burst includes telescope slew time periods, the fitting uses an average response file made from multiple 5-s response files through out the slew time plus single time preiod for the non-slew times, and weighted by the total counts in the corresponding time period using addrmf. An average response file is needed becuase a spectral fit using the pre-slew DRM will introduce some errors in both a spectral shape and a normalization if the PHA file contains a lot of the slew/post-slew time interval.
- 3) For fits to more complicated models (e.g. a power-law over a cutoff power-law), the BAT team has decided to require a chi-square improvement of more than 6 for each extra dof.
Time averaged spectrum fit using the average DRM
Power-law model
Time interval is from 1.624 sec. to 267.996 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.72532 ( -0.0833578 0.0841517 )
Norm@50keV : 1.83911E-03 ( -8.86058e-05 8.82366e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 70.96 using 59 PHA bins.
# Reduced chi-squared = 1.245 for 57 degrees of freedom
# Null hypothesis probability = 1.011420e-01
Photon flux (15-150 keV) in 266.4 sec: 0.246455 ( -0.0117941 0.0118179 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.52784e-06 ( -2.26652e-07 2.27615e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.624 sec. to 267.996 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.34163 ( -0.362809 0.334474 )
Epeak [keV] : 83.5637 ( -19.8877 191.003 )
Norm@50keV : 2.89138E-03 ( -0.000922551 0.00150532 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 67.09 using 59 PHA bins.
# Reduced chi-squared = 1.198 for 56 degrees of freedom
# Null hypothesis probability = 1.473971e-01
Photon flux (15-150 keV) in 266.4 sec: 0.241047 ( -0.012648 0.012661 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.38825e-06 ( -2.58008e-07 2.58168e-07 ) ergs/cm2
Band function
Time interval is from 1.624 sec. to 267.996 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.17689 ( -0.461256 1.17125 )
beta : -1.98345 ( 1.98049 0.25078 )
Epeak [keV] : 66.8800 ( -43.8336 117.045 )
Norm@50keV : 3.63031E-03 ( -0.00158202 0.345927 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.52 using 59 PHA bins.
# Reduced chi-squared = 1.209 for 55 degrees of freedom
# Null hypothesis probability = 1.373404e-01
Photon flux (15-150 keV) in 266.4 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 4.39227e-06 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 13.2962 ( )
R^2/D10^2 : 4.00797E-02 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 163.37 using 59 PHA bins.
# Reduced chi-squared = 2.8662 for 57 degrees of freedom
# Null hypothesis probability = 3.341955e-12
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.001e-07 3.463e-08
25- 50 1.412e-06 7.686e-08
50-150 1.598e-06 1.479e-07
15-150 3.410e-06 1.825e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 130.310 (-25.3844 30.2452)
Norm : 1.02142 (-0.0589144 0.0736036)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 67.20 using 59 PHA bins.
# Reduced chi-squared = 1.179 for 57 degrees of freedom
# Null hypothesis probability = 1.672283e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.059e-07 5.421e-08
25- 50 1.280e-06 8.711e-08
50-150 2.377e-06 6.896e-07
15-150 4.363e-06 7.219e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 6.39985 (-1.1294 1.32106)
R1^2/D10^2 : 0.366454 (-0.168888 0.375354)
kT2 [keV] : 21.9105 (-3.14982 5.21702)
R2^2/D10^2 : 4.97406E-03 (-0.00281196 0.00432673)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 71.79 using 59 PHA bins.
# Reduced chi-squared = 1.305 for 55 degrees of freedom
# Null hypothesis probability = 6.378272e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.975e-07 1.118e-07
25- 50 1.285e-06 1.574e-07
50-150 2.310e-06 4.024e-07
15-150 4.293e-06 6.447e-07
Peak spectrum fit
Power-law model
Time interval is from 8.408 sec. to 9.408 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.07164 ( -0.395927 0.362549 )
Norm@50keV : 8.37679E-03 ( -0.00207923 0.00204806 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.44 using 59 PHA bins.
# Reduced chi-squared = 1.131 for 57 degrees of freedom
# Null hypothesis probability = 2.324737e-01
Photon flux (15-150 keV) in 1 sec: 0.968963 ( -0.24625 0.249839 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.83912e-08 ( -2.12724e-08 2.13453e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 8.408 sec. to 9.408 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.486965 ( -2.79894 1.66735 )
Epeak [keV] : 92.3355 ( -28.1256 -92.3222 )
Norm@50keV : 4.07174E-02 ( -0.040736 0.474187 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.03 using 59 PHA bins.
# Reduced chi-squared = 1.108 for 56 degrees of freedom
# Null hypothesis probability = 2.699571e-01
Photon flux (15-150 keV) in 1 sec: 0.927582 ( -0.248263 0.253678 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.46615e-08 ( -2.2428e-08 2.23515e-08 ) ergs/cm2
Band function
Time interval is from 8.408 sec. to 9.408 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 5.00000 ( -5.70249 -5 )
beta : -1.34892 ( -0.967697 0.479637 )
Epeak [keV] : 36.1034 ( -15.2214 19.1566 )
Norm@50keV : 80.8242 ( -18.3644 1745.79 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.57 using 59 PHA bins.
# Reduced chi-squared = 1.119 for 55 degrees of freedom
# Null hypothesis probability = 2.528069e-01
Photon flux (15-150 keV) in 1 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 8.50252e-08 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 20.7783 (-4.617 6.79381)
R^2/D10^2 : 4.37039E-02 (-0.0268757 0.0581973)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.53 using 59 PHA bins.
# Reduced chi-squared = 1.097 for 57 degrees of freedom
# Null hypothesis probability = 2.862983e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.581e-09 1.777e-09
25- 50 1.828e-08 7.010e-09
50-150 5.878e-08 2.633e-08
15-150 8.065e-08 3.641e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 ( )
Norm : 4.18398 (-1.03079 1.03058)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 68.53 using 59 PHA bins.
# Reduced chi-squared = 1.202 for 57 degrees of freedom
# Null hypothesis probability = 1.409690e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.043e-08 6.265e-09
25- 50 2.006e-08 1.199e-08
50-150 4.399e-08 2.608e-08
15-150 7.448e-08 4.343e-08
Double BB
#Fit statistic : Chi-Squared = 61.88 using 59 PHA bins.
#Fit statistic : Chi-Squared = 61.86 using 59 PHA bins.
#Fit statistic : Chi-Squared = 61.84 using 59 PHA bins.
# Reduced chi-squared = 1.126 for 55 degrees of freedom
# Reduced chi-squared = 1.125 for 55 degrees of freedom
# Reduced chi-squared = 1.125 for 55 degrees of freedom
# Reduced chi-squared = 1.125 for 55 degrees of freedom
# Reduced chi-squared = 1.124 for 55 degrees of freedom
# Null hypothesis probability = 2.419878e-01
# Null hypothesis probability = 2.436684e-01
# Null hypothesis probability = 2.440668e-01
# Null hypothesis probability = 2.445617e-01
# Null hypothesis probability = 2.451454e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.747e-09 4.021e-09
25- 50 1.941e-08 1.913e-08
50-150 6.090e-08 6.610e-08
15-150 8.506e-08 7.470e-08
Pre-slew spectrum (Pre-slew PHA with pre-slew DRM)
Power-law model
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.26465 ( -0.11978 0.117646 )
Norm@50keV : 3.56573E-03 ( -0.000253768 0.000253435 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.72 using 59 PHA bins.
# Reduced chi-squared = 1.100 for 57 degrees of freedom
# Null hypothesis probability = 2.806799e-01
Photon flux (15-150 keV) in 59.18 sec: 0.422755 ( -0.0322839 0.0324052 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.10383e-06 ( -1.54189e-07 1.54449e-07 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.674494 ( -0.560189 0.495385 )
Epeak [keV] : 124.973 ( -35.8662 305.815 )
Norm@50keV : 6.67218E-03 ( -0.00267684 0.00514374 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.52 using 59 PHA bins.
# Reduced chi-squared = 1.045 for 56 degrees of freedom
# Null hypothesis probability = 3.831132e-01
Photon flux (15-150 keV) in 59.18 sec: 0.412751 ( -0.033335 0.033438 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.0521e-06 ( -1.63899e-07 1.62692e-07 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 1.79863 ( -2.5334 -1.80112 )
beta : -1.45820 ( 1.45815 0.189817 )
Epeak [keV] : 42.3069 ( -11.2756 81.3637 )
Norm@50keV : 0.285504 ( -0.289686 26.9133 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.10 using 59 PHA bins.
# Reduced chi-squared = 1.020 for 55 degrees of freedom
# Null hypothesis probability = 4.334658e-01
Photon flux (15-150 keV) in 59.18 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
S(25-50 keV) vs. S(50-100 keV) plot
S(25-50 keV) = 1.24e-06
S(50-100 keV) = 1.50e-06
T90 vs. Hardness ratio plot
T90 = 230.507999956608 sec.
Hardness ratio (energy fluence ratio) = 1.20968
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.22846
Count Ratio (50-100 keV) / (15-25 keV) = 0.858568
Mask shadow pattern
IMX = 9.652878819943155E-01, IMY = 9.332824055802651E-03
TIME vs. PHA plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 12.160000
TIME vs. DetID plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 12.160000
100 us light curve (15-350 keV)
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 12.160000
Spacecraft aspect plot
Bright source in the pre-burst/pre-slew/post-slew images
Pre-burst image of 15-350 keV band
Time interval of the image:
-239.296000 1.624000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.5418 -40.6005 4.6 50.9 23.3 1.9344 2.5 2.8 Vela X-1
170.5743 -60.6067 5.0 47.9 -15.4 0.8009 2.3 7.7 Cen X-3
186.3186 -62.7987 178.7 48.9 -25.7 -0.0241 -0.1 9.4 GX 301-2
172.3388 30.5519 2.2 46.2 139.1 3.8983 5.2 ------ UNKNOWN
133.6641 -51.7266 2.6 55.9 10.8 4.5460 4.4 ------ UNKNOWN
202.4839 -5.9203 3.0 18.6 -139.0 0.6835 3.8 ------ UNKNOWN
225.2939 31.0733 2.2 59.1 -165.4 7.3814 5.4 ------ UNKNOWN
162.5097 -71.8780 3.1 59.6 -17.1 4.5594 3.7 ------ UNKNOWN
193.0761 -62.9208 3.3 49.3 -29.8 1.3724 3.6 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
1.624000 60.804600
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.4848 -40.4281 5.5 50.9 23.5 -0.7477 -2.1 7.9 Vela X-1
170.2624 -60.5589 3.9 47.9 -15.2 0.4670 3.0 4.2 Cen X-3
186.3233 -62.8733 10.3 49.0 -25.7 0.2186 1.1 11.0 GX 301-2
157.5419 -51.7953 0.6 44.0 -0.6 3.0019 20.1 ------ UNKNOWN
165.1126 -70.2632 2.2 57.7 -17.2 2.0820 5.2 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
148.604600 585.904650
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.5866 -40.5201 1.8 18.8 6.5 1.7071 6.6 3.4 Vela X-1
170.4059 -60.5864 1.6 11.3 -145.5 2.1937 7.1 3.4 Cen X-3
186.3369 -62.8533 6.8 18.8 -154.5 0.5168 1.7 10.1 GX 301-2
145.1730 -16.6425 3.5 36.5 48.2 1.7409 3.3 ------ UNKNOWN
157.5321 -51.7906 0.8 0.0 -81.0 3.5937 13.8 ------ UNKNOWN
50.1829 -81.9327 3.3 41.2 -99.9 6.1717 3.5 ------ UNKNOWN
Plot creation:
Sat May 30 17:14:02 EDT 2015